at first 与 first of all 有什么区别?

Question

at first 与 first of all 有什么区别?

Answer 1

at first是指“最初”,“最开始”,
例子at first I thought he was a good person,but later I found out he is a jerk.最初我以为他是个好人,后来我发现他是个混蛋.
first of all是指次序上的“首先”“第一”这个意思
例子：first of all,I want to thank you all for coming.首先,我要感谢各位的光临.
所以这两次表达是有区别的.